can risa or staad be used to model pipe underground for dynamic seismic?
can risa or staad be used to model pipe underground for dynamic seismic?
(OP)
can risa or staad be used to model pipe underground for dynamic seismic?
any sample of this?
any sample of this?
RE: can risa or staad be used to model pipe underground for dynamic seismic?
RE: can risa or staad be used to model pipe underground for dynamic seismic?
If you're looking for non-linear soil modeling then the answer would be no. Those programs are primarily for elastic materials.
RE: can risa or staad be used to model pipe underground for dynamic seismic?
RE: can risa or staad be used to model pipe underground for dynamic seismic?
RE: can risa or staad be used to model pipe underground for dynamic seismic?
You're describing an eigenvalue or modal analysis. I'm not sure that would work. I don't think you can use nonlinear compression only supports with dynamic analysis. Also, while there are assumptions STAAD can make in eigenvalue analysis to allow for variable damping, I don't think STAAD allows you to do the same for the stiffness. Dynamic soil behavior is all about impedance (variable stiffness and damping). I could be wrong, but I think you're stuck with a nonlinear inelastic time-history analysis - which STAAD doesn't handle.
RE: can risa or staad be used to model pipe underground for dynamic seismic?
The option I described is applicable not only to eigensolution but to dynamic analysis like time history as well. While defining the time history, you need to choose the modal damping option (MDAMP). However as I mentioned in my post, nonlinear soil stiffness cannot be defined in a dynamic analysis and you cannot define compression only in a dynamic analysis either.
RE: can risa or staad be used to model pipe underground for dynamic seismic?
RE: can risa or staad be used to model pipe underground for dynamic seismic?
At least for reinforced concrete, the structure above ground will be at least as non-linear as the soil/pipe system below ground. If an analysis based on linear properties is considered suitable for the above ground structure, why isn't it suitable for the underground structure?
If a non-linear dynamic analysis is required there are a lot of options in between Risa/Staad and Abaqus. I know Strand7 will do this, and I am sure there are many others.
Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/